WALWORTH COUNTY, WI (WTAQ) - A Lake Geneva area couple pleaded not guilty Wednesday to severely abusing their six adopted children – three of whom came from Russia.

Martin and Kathleen O’Brien, both 49, are charged in Walworth County with a total of 23 counts of felony child abuse and misdemeanor disorderly conduct. The couple has four children of their own, plus the six they adopted.

The adopted children told authorities that the O’Briens made them kneel on sharp rocks, stand barefoot in snow, and not read or go to school – while the biological children were treated much better.

The case drew media attention in Russia, after the country tightened its adoption rules for U.S. citizens after 19 Russian children had died in American homes over the last decade.

Also, the Milwaukee Journal Sentinel had said Walworth County had not filed a required report with the state about the case until the paper asked state officials about it.

Meanwhile, the O’Briens remain free on signature bonds. They’re due back in court November 21st, when a judge will consider pre-trial requests.